1. Field of the Invention
The present invention relates to a device for moulding articles of composite materials. More particularly, the present invention relates to a device comprising a female half-mould designed to receive a reinforcer fibrous material, a male half-mould designed to get tightly closed onto said female half-mould and feeding means in order to feed the suitable resin for impregnating the reinforcer material.
2. Description of the Related Art
The presently used processes for moulding articles of composite materials (based on a thermosetting resin and a reinforcer material) provide for a pre-catalysed resin to be injected into a mould in which a reinforcer material was previously charged, as interlaced fibres (fabric), or as a non woven fabric (mat).
The equipment used in such technology, commonly referred to as "RTM (Resin Transfer Moulding)", require that the resin is considerably pressurized in order to enable the reinforcer material to be completely impregnated, as well as a cleaning system for the pre-catalysed resin injection nozzle in order to prevent said nozzle from accidentally clogging. The second drawback was obviated by using separate nozzles for feeding non-pre-catalysed resin and catalyst, leading into a mixing chamber inside which a self-cleaning ram is slidingly assembled. Such a solution, disclosed in European Patent Application EP-A-529,651, requires high injection pressures which, besides increasing the complexity and cost of equipment used, implies the risk that a back mixing of resin and catalyst takes place inside said nozzles.
A further, well known, moulding technique, referred to as "Compression Moulding" provides for the pre-catalysed resin to be fed into a half-mould containing the reinforcer material, followed by closing the half-mould, with consequent reinforcer element impregnation. Such a technique, poorly automated, requires that the resin and catalyst are pre-mixed and a predetermined Mount of resin/catalyst mixture is subsequently added to the female half-mould. Clearly, such a technique is neither suitable for high throughput rates (fast manufacturing cycles), nor does it allow highly reproducible results to be achieved.